


Like The Tide

by Ourliazo



Category: Harry Potter - J. K. Rowling, Katekyou Hitman Reborn!
Genre: Adult Reborn - Freeform, BAMF Harry Potter, Family-ish, Gen, Humour, Master of Death Harry Potter, Pre-Arcobaleno Curse, Protective Harry Potter, Reborn Is A Brat
Language: English
Status: Completed
Published: 2019-11-23
Updated: 2020-07-07
Packaged: 2021-02-26 00:35:23
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 2,641
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21534568
Author URL: https://archiveofourown.org/users/Ourliazo/pseuds/Ourliazo
Summary: Harry can see death now, in this new world. Can see faint imprints clinging to people, making their shadows just that bit darker, just a touch deeper. Reborn is like the tide, dragging a cresting wave as he walks, filling the streets with a writhing black mass of half faded faces.(In the end, it comes down to the fact that Reborn really needs to stop killing things, so grandpa Harry takes it upon himself to raise the young man. Reborn even humours him sometimes, which is progress.)
Relationships: Harry Potter & Reborn
Comments: 54
Kudos: 1334
Collections: Clever Crossovers & Fantastic Fusions, Harry Potter





	1. Chapter 1

Harry has been in this new place, this new world, for almost a year now. He's been in Italy specifically for a week, and today he chose to sit outside a café down a quiet street just to watch people go by.

Watching is pretty much all that he's been doing, here on this next great adventure. It would be nice if someone told him what he's doing here, why he didn't die of old age like he was supposed to, how he moved into this non-magical world.

But it's not surprising that Harry didn't get an instruction manual either. He's a teenager again, maybe eighteen - maybe seventeen. Should have burned the Hallows, he thinks, should have done a better job of getting rid of them.

That's on him though so he's mostly just disappointed with himself.

He hung around England for a very long time, mostly wandering. He did panic at first, waking up on rolling green hills where Hogwarts should have been, but he's a hundred and thirty-two this year so nothing much fazes him.

A woman passes by his shoulder on the street and Harry leans away, the metal folding chair squeaking underneath him. Her shadow rises up briefly into indistinct shapes on the footpath before collapsing in on itself and settling.

Harry likes to think his powers are just getting stronger but it's probably because people here in Italy are just more awful. The deaths cling to them, hide in their shadows and clutch at their heels to slow them down, drag them down. Harry has seen darkened shadows, or things twisting up out of the blackness. He's even seen indistinct faces looking over a person's shoulder.

Harry has never before seen a wave of death cresting over the two storey buildings of a street, opaque pitch black blocking out the sun.

He drops his tea. The cup clatters on the round plastic table, the liquid soaking the stack of napkins and spilling over the edge onto Harry's lap. His focus narrows, the world blurring in his periphery as the tide washes closer.

The figures are all a deep black, bleeding into each other but their sorrow and rage so strong that Harry can make out eyes and lips, details of one hair style or another, reaching fingers and clawed hands.

A whipcord thin man turns the corner and strolls down the street, hands in pockets, hat tipped low to shade his eyes. The tide swells behind him, billowing out like a cloak of death as the souls grasp at his shoulders.

The man looks up and after a brief scan of the area his gaze locks onto Harry's. The man smiles, charming and breathtakingly beautiful even as his shadow encompasses the whole street.

Harry's hands are shaking. He lowers them onto the table, into the spilled tea. His cup has fallen to the ground at some point. The world is silent, but pressure is holding his body down, making it hard to breathe.

The man darts a quick look up and down the quiet street before crossing the two-lane road to Harry's side. He stops beside the table and bends down to pick up the fallen cup.

The wave crashes over them, circling around behind Harry and cutting off the sky. He can't see anything past the writhing black mass of people surging out and being dragged back in. There's a woman. She whispers something into the man's ear, blood dripping down her forehead from a perfect, neat little hole.

( _monster, beast, you twisted thing)_

The man smirks like he hears something funny.

The cup is placed in front of Harry and the man sits down on the metal folding chair opposite. The fractured shadows fall to their knees at his feet like praying to a God, like begging mercy from a Devil.

"May I sit here?" the man asks, already making himself comfortable. He must think himself amusing because there's laughter in his eyes.

"How did you do this?" Harry murmurs, struggling to breathe when the dome pushes in. It's silent, they don't make noise, but their presence is so loud that Harry is surprised he couldn't sense them sooner. He can feel them now, they're hurting so much.

"My name is Reborn," the man says easily, ignoring Harry's question. "What's yours?"

"How many have you killed?"

Reborn inhales sharply, his eyelashes fluttering. "Oh, _hundreds_ ," he breathes out, biting down on the word like he's tearing into something.

"Why?" Harry demands. "What could possibly make you kill so many?"

"Well, after that first one, I just couldn't stop myself," Reborn chuckles. "I have a bit of a problem, I know, but no one has complained so far." He shrugs. "It's not like the dead can talk."

Harry shakes his head slowly. "You're holding onto them. They can't leave."

"They're mine." Reborn blinks. "They're not allowed to leave." He shifts forward in his seat, leaning over the table.

Harry is frozen where his is and the man places a hand over Harry's. There's another too, a cold hand holding the back of Reborn's, finger laced with his like a lover. Harry snatches his hand back, puts both in his lap.

Reborn doesn't seem to mind. "Can you see them?" Reborn has noticed Harry's flickered glances to the side. "Are they as lovely as I've always imagined?"

"It's disgusting." Harry's lips twist down. "They're suffering."

"And I assure you, they deserve it," Reborn promises, looking _oh_ so very saddened by it all.

Harry grits his teeth. "Don't pretend you're doing this for anything but your own pleasure. People deserve rest after death, no matter what they did in life."

Reborn places an elbow on the table, tucking knuckles under his chin. Fingers, not his, brush through the man's hair and skim along his jaw, wrapping around his throat and trying to choke him.

Reborn rolls his eyes. "Oh, and I suppose you'll tell me what a bad boy I've been next? Save the morals for a civilian, you're in Mafia territory now."

Harry slams a hand down onto the table and the tar explodes outwards. The shadows flicker and the edges tear, everything dispersing into nothingness under the power of the Master of Death.

Reborn tips backwards in his chair, elbow slipping off the table and hands falling into his lap. His lips part but no sound comes out and he stares at Harry with big black eyes, the sudden sunlight turning his skin golden.

Reborn looks smaller now without the cloak of tar. He fits into the crooked metal folding chair, his body slim and the obviously tailored suit is cut tight, tucked neatly around him. He can't be more than twenty-three, for all that the man has killed so many.

"Are they…?" Reborn whispers.

"Gone," Harry grits out, nails scrapping against the rough plastic tabletop. "Do what you will with the living but death is not something you can play with." His hand curls into a fist. "Let them rest."

Reborn laughs, a little breathless because he must have felt the magic cut through him, dig in and twist to uproot the souls he's devoured. Even if the man didn't let himself flinch from it, that must have hurt. Reborn shivers when a cool breeze rolls past, probably cold now without his blanket.

A child, Harry thinks, just a little boy who wants to play. Harry's great grandkids are older than this man. He suddenly feels very old.

Harry picks up some half-soaked napkins and tries to blot out the tea from his clothes. "What would you like?"

Reborn blinks.

Harry gives up and drops the napkins back on the table with a wet _splat_. "Do you drink tea? Coffee?"

"Espresso," Reborn murmurs.

Harry waves over a staff member with a smile and orders more tea and an espresso for the serial killer.

"So," Harry says when the waiter heads back to the counter. "I've been meaning to ask someone about the fire."

Reborn turns away but peers at Harry out of the corner of his eye. "You're either very good at faking or you're not upset anymore."

Harry waves a hand through the air. "Don't hold on to them, that's all I ask."

Reborn faces him again and pastes on that same charming smile that he used at the start. It sharpens his cheekbones, makes his eyes shine and adds a little seductiveness from the quirk of his lips. "Tell me how you did that and I'll tell you about the fire."

Reborn is adorable. Ginny would have loved him.

Harry sighs but it's not like there's a Statute of Secrecy here. "Sure."

**Notes for the Chapter:**

> The majority of the Mafia stay far away from Harry, thinking Reborn will kill them if they upset his 'little brother'.
> 
> On the other hand, all the powerhouses and ancient, Eldritch horrors treat Reborn like Harry's little boy. Because technically he is. And when he gets all murderous they coo at him.


	2. Chapter 2

"You…" Harry trails off. He drops the wooden spoon into the pan and turns fully to look at Reborn sitting at the dining table. "The yellow heals people? _You_ heal people?"

"No," Reborn says firmly. "I can activate cells, which sometimes other Suns use to heal. I don't do that. I kill."

"I'm aware," Harry says wryly. "It's been a week and you already have a little-" He gestures at the shadow stretching out behind Reborn.

"I'm not holding onto him," Reborn says immediately, picking his feet up off the floor like that will create enough distance to absolve him of his crime.

"This one just likes you," Harry does admit. He shoos the shadow and it squidges around but doesn't leave.

Reborn puts his feet down. "Can I keep it?"

Harry slaps a hand down onto the counter and the shadow vanishes.

Reborn clicks his tongue. "Damn."

"Maybe just stop killing people?"

Reborn laughs and Harry turns back to the stove.

* * *

Harry wakes up to find Reborn in his bed, staring at him, the man lying on his side and still fully dressed. He didn't even take his hat or shoes off.

"What," Harry deadpans.

"You know that Skull guy I was talking about?" Reborn begins. "Well, so, I shot him. But then he didn't die. And I was wondering if maybe he was your friend?"

"You are my only friend," Harry tells the mass murderer. "Though, _Merlin_ , I wish that wasn't true."

Reborn brightens up, but it's like shutting the curtains only to turn on the lights, completely artificial and shallow. "Aw, you're my only friend too. Because I killed the last one a month ago." He shrugs. "And yes, maybe I could go make more but I've been busy with the whole Checker Face thing lately."

Harry rolls away and tries to get back to sleep because it's currently three-something in the morning.

* * *

"Grandpa!"

Harry keeps walking and greatly regrets telling Reborn more about his life. To be fair, Reborn has a sliver tongue, and Harry is a sucker for those small smiles even when he knows they're not genuine.

The hitman slides up beside Harry and grabs the teenager's hand. "Grandpa, where are we going today?"

"I'm meeting with Bermuda," Harry says. "I don't know what you're doing though, so off you go."

"Vindice," Reborn sneers in annoyance at hearing the name.

"They're the only ones my age around here," Harry reminds Reborn. "Maybe I'd like you more if you stopped running around so energetically."

"I hope I die before I get old like you."

Harry blinks and it takes a moment to register. "You little shit."

* * *

Kawahira tenses and whirls around. "Ah. I suppose the Vindice have tattled."

Harry stands with his hands in his pockets, gripping the Elder wand. "We should talk."

The Arcobaleno wander around the mountain's summit further away, bitching loudly to each other as they fight over the map to find the supposed 'treasure' Kawahira sent them to find.

Reborn shoves Verde into Fon and then runs to hide behind Lal. There's a dark shadow crawling up his legs. Harry will have to take care of that when his boy gets home.

Kawahira watches Reborn as well. "Surely you know sacrifice."

"I do," Harry muses. "But only _self_ -sacrifice. If you try to take my darling serial killer, then the world can burn for all I care."

"It will." Kawahira gazes at Harry with a millennia weighing down his shoulders. "It will all burn. Not just this world but the entire multiverse."

"I don't want that," Harry insists. "But your solution is lazy. It's inefficient, it's cruel and you are one dumb son of a bitch to have kept it going for this long."

Mist flames rise up and reality twists around Kawahira's form. The Checker Face disguise falls away and the not-quite human smiles. "It's easy to criticise, isn't it? Give me something better then, or get out of my way."

Harry smirks because maybe he's been spending too much time with Reborn. "Step back, I'm about to show you a little magic trick."

* * *

Harry steps out of Bermuda's warp portal and into his living room only to find Reborn sitting on his couch.

There are crunching, slurping noises as a thing with too many limbs and too little skin eagerly devours two corpses on a thick plastic sheet set out in the middle of the room.

"Have fun at the nursing home?" Reborn huffs. "I could have picked you up instead."

"You don't own a car."

"I own a Skull."

Harry shakes his head. "Never mind. What is that?" He points at the Eldritch horror on the carpet.

Reborn blinks. "Is that not yours?"

Harry blinks back. "Why would it be mine?"

Reborn opens his mouth, closes it and then tries again. "It's been following me for a while. It eats my dead things. It has a morbid sense of humour."

Harry takes a deep breath. "Which of those three things reminds you of me, exactly?"

Reborn looks away.

"This is not on me," Harry says adamantly. "This is you, this is _your_ weirdness."

* * *

Colonnello looks the hitman up and down when Reborn steps through the door of the Arcobaleno manor. "Why are you moping? Harry didn't feed you again?"

"Don't sass me, Nello, I'll pistol whip you." Reborn drops down onto the couch beside the blond in a huff.

Colonnello waves him off because after a while Reborn seems more like some homicidal pet lizard than an actual threat. "Where's your little brother? Is he at your uncle Kawahira's again?"

"Checker Face isn't my anything," Reborn quickly responds. "And Harry is over a hundred and thirty, by the way."

"Listen," Colonnello sighs. "I'm stupid, but I'm not that stupid."

"That's debatable."

Colonnello rolls his eyes. "Oh and your uncle Bermuda warped in this morning. He said that-"

"Not my anything either," Reborn grumbles. "I'd kill them all if Harry wouldn't whine at me for it."

Skull looks over his shoulder from where he's lying on the carpet on his stomach. He looks at Reborn's legs. "Maybe you should cut back on the killing for a while."

Reborn grumpily pats at his legs like that's going to actually chase the souls away.

Skull squints a bit. "Is that … a child?"

Reborn points a finger at him. "I don't tell you how to do your stupid bike flips, don't tell me where to point my gun."

Colonnello raises an eyebrow at him. "You killed a kid?"

Reborn's hand comes down on the blond's leg as a claw and the soldier yelps in pain. Reborn leans in close, eyes like an empty void. "Harry will never know."

* * *

" _Voldemort was a better man than you!_ " Harry screams.

"At least I could have _killed the baby,_ " Reborn retorts sharply.

Harry gestures with jerky motions towards Reborn's shadow. "Yeah, as you clearly demonstrated!" He grits his teeth and pulls back, trying to calm himself down. "You are going straight to your uncle Bermuda's."

Reborn gapes. "You can't put me in prison!"

"You are being grounded, young man!"

"I am a fully grown adult!"

"Come talk to me when you're not _toddling around on two decades!_ "


End file.
